1. Field of the Invention
The present invention relates to a filler pipe structure for connecting an fuel filler neck of a vehicle with a fuel tank inside thereof and for leading fuel supplied from the fuel filler neck by an oil filling gun and the like to the fuel tank inside, and particularly, to the filler pipe structure used in the vehicle (hereinafter referred to as “center tank vehicle”) where the fuel tank is substantially arranged at a center of the vehicle.
2. Description of the Related Art
Conventionally, a center tank vehicle where a fuel tank is arranged below a front seat of the vehicle is known (for example, see paragraph 0024 and FIG. 1 of Japanese Patent Laid-Open Publication No. 2000-85382). Such the center tank vehicle can ensure a rear compartment of the vehicle larger, compared to a vehicle where a fuel tank is arranged at rear.
On the other hand, nowadays a vehicle with an ORVR (Onboard Refueling Vapor Recovery) appears (for example, see paragraphs 0018 to 0020 and FIG. 1 of Japanese Patent Laid-Open Publication Hei 8-21317). The ORVR is something for preventing a fuel evaporation gas generated within a fuel tank from being dispersed in the atmosphere through a filler neck when fuel is filled in the fuel tank. As such the ORVR, for example, can be cited one configured of a fuel evaporation gas reflux pipe for connecting a fuel tank inside and a filler pipe in a vicinity of a filler neck, another one where a canister where an adsorbent for adsorbing a fuel evaporation gas is housed is attached to a fuel tank through a communicating pipe, and the like. Out of these, when supplying fuel from the filler neck, the one configured of the fuel evaporation gas reflux pipe is designed to reduce an evaporating amount of fuel in the air sucked together with the fuel from the filler neck by refluxing a saturated fuel evaporation gas generated in the fuel tank via a route of the fuel evaporation gas reflux pipe, filler pipe, and fuel tank. In addition, the another one where the canister is attached to the fuel tank is designed to capture the fuel evaporation gas led from the fuel tank through the communication pipe by the adsorbent.
In this connection, because in the center tank vehicle a distance from the filler neck arranged at rear of the vehicle body to the fuel tank becomes longer, a filler pipe for connecting the fuel tank inside and the filler neck becomes longer. As a result, an oil filling resistance of the filler pipe augments in filling oil.
In addition, in a vehicle equipped with the ORVR a fuel evaporation gas within the fuel tank is sent into the fuel evaporation gas reflux pipe or the fuel evaporation gas is sent into the canister by using a head difference of the fuel filled in the filler pipe from the filler neck. As a result, in the vehicle equipped with the ORVR the oil filling resistance of the filler pipe augments in filling oil.
Accordingly, attempting to equip the ORVR with a center tank vehicle, it is foreseen that the oil filling resistance of the filler pipe markedly augments in filling oil. As a result, there is a possibility that a smooth oil filling is prevented.
Consequently, in order to solve such the problem can be thought a fuel tank structure that is designed to protrude a part of a rear end of the fuel tank toward a rear so that a plan view shape thereof becomes a convex shape, and to connect the filler pipe to the protruded part. In accordance with such the fuel tank structure, because the filler pipe for connecting the fuel tank inside and the filler neck is shortened, it is expected that the oil filling resistance of the filler pipe is reduced in filling oil, and that a smooth oil filling results in being realized. However, because in the fuel tank structure the shape of the fuel tank becomes complicated, it is foreseen that a yield of the fuel tank obtained worsens.
Consequently, a filler pipe structure is strongly requested that can realize a smooth oil filling even in a center tank vehicle equipped with the ORVR using a usual fuel tank of a good yield.